3781813 has 8 divisors (see below), whose sum is σ = 4334528. Its totient is φ = 3232224.

The previous prime is 3781801. The next prime is 3781819. The reversal of 3781813 is 3181873.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3781813 - 2⁵ = 3781781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3781819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3145 + ... + 4177.

It is an arithmetic number, because the mean of its divisors is an integer number (541816).

Almost surely, 2^3781813 is an apocalyptic number.

It is an amenable number.

3781813 is a deficient number, since it is larger than the sum of its proper divisors (552715).

3781813 is a wasteful number, since it uses less digits than its factorization.

3781813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1563.

The product of its digits is 4032, while the sum is 31.

The square root of 3781813 is about 1944.6884069177. The cubic root of 3781813 is about 155.7997238151.

The spelling of 3781813 in words is "three million, seven hundred eighty-one thousand, eight hundred thirteen".